JPH10159474A - Excavation method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently excavate ground, and increase the working efficiency even if there is a huge boulder stone or rocks which are obstacles in the usual excavation, while reducing the resistance acting on the rod during the work excavation and reduce the consumption rate of the excavating head and shorten the construction period and realize an economically perfect excavation work. SOLUTION: An agitating and consolidation rod 18 in which a troweling plate 16 and a propeller type agitation blade 17 generating an upflow stream are attached, are connected onto an excavation head 14. And further, a bar-form additional rod 19 is connected to the agitating and consolidating rod 18. And a hammer rod 22 is exposed to position at the central part of the excavation head 14 to use an excavating device in which a down-the-hole hammer 21 is assembled. The soil excavated by the bit 15 of the excavation head 14 is used to consolidate the hole wall by the troweling plate 16 so as not to increase the excavation resistance even if the excavation depth becomes large. The excavated muck generated by the down-the-hole hammer 21 is applied to consolidate the hole wall by the troweling plate 16 not to bring it up onto the ground.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for excavating pile holes as foundation work in the fields of construction and civil engineering.

[0002]

2. Description of the Related Art A typical excavator for excavating a pile hole is an earth auger, which is well known, as shown in FIG.
Drive unit 4 consisting of hydraulic or electric motor and reduction gear
A screw rod 5 provided with a screw blade 5b, which is a spiral blade connected to the rod 5a, is connected to and suspended from the rotary drive shaft, and an auger head 6 is provided at the tip thereof.

A leader mast 2 is erected on a heavy machine 1 such as a crawler, and the driving device 4 is suspended from a top sheave 3 of the leader mast 2. And take it out. In addition, the driving device 4 is a leader mast 2
And moves up and down along the leader mast 2. 27 in the figure is a middle and lower steady rest,
5 'is a spare screw rod.

When the driving device 4 is driven in this manner,
The excavation is performed by the screw rod 5 and the auger head 6 rotating, and the auger head 6 guiding the screw rod 5 into the ground.

[0005]

However, in the conventional earth auger as shown in FIG. 4 described above, the whole is inserted into the ground in the shape of a cone, but at this time, the earth and sand carried out to the ground is These auger head 6 and screw rod 5
Is just the volume integral of. This is because the earth and sand excavated by the auger head 6 is in the form of particles and moves freely in the hole, so that the screw blade 5b cannot be expected to have a conveying action like a screw conveyor.

When the excavated soil is viscous, the soil sandwiched between the screw blades 5b is removed by the screw rod 5b.
May be transported to the ground with the lifting.

Further, in the conventional earth auger, the collapse of the drilled hole is simultaneously applied as a resistance,
A large excavation load is applied, which increases with increasing depth.

In addition to such earth augers, down-the-hole hammers are also used for excavating pile holes. As is well known, a down-the-hole hammer excavates rock with the impact force of a tip bit by reciprocating a hammer piston with air from a compressor. Usually, the down-the-hole hammer is specialized in excavation, and the injection of cement milk relies on pouring after excavation. However, in JP-A-6-213870, as shown in FIG. Some mortars for cement and cement milk can be injected and filled from the tip of the bit. In this Japanese Patent Application Laid-Open No. 6-213870, a spiral blade 9 is provided on the outer periphery of a main body 8 above a hammer head 11, and a passage for introducing compressed air and a passage for introducing a fluid such as cement milk are formed in the main body 8. The compressed air introduction port 10a and the fluid introduction port 10b for cement milk or the like face the connection portion of the main body 8 as its ends.

Further, Japanese Patent Application Laid-Open No. 8-246778 discloses an improvement on the above-mentioned Japanese Patent Application Laid-Open No. 6-213870, which further includes a support extending radially beyond the outer peripheral edge of the hammer head 11, as shown in FIG. A plate 12 is mounted, and a drill bit 13 is provided at the lower end of the support plate 12.

[0010] Japanese Patent Application Laid-Open No. 6-213870 and Japanese Patent Application Laid-Open
The down-the-hole hammer shown in 8-246778 is an improvement of the original down-the-hole hammer,
As in the case of the earth auger, the screw blade 5b
With the spiral blade 9 similar to that described above, it is not possible to efficiently carry the ground and the like crushed by the bit of the hammer head 11 to the ground portion and carry it out.

Further, as in the case of the earth auger, since the collapse of the excavated hole is simultaneously applied as a resistance, there is a disadvantage that a large excavation load is applied and the load increases as the depth increases.

The support plate 12 having the drill bit 13 disclosed in Japanese Patent Application Laid-Open No. Hei 8-246778 expands the bore of the drill hole, but the hammer head 11 first drills the hole having the outer diameter. The surrounding area of the drilling hole is later drilled further by the drilling bit 13 attached to the support plate 12.
It is premised on step excavation, and there is no technical idea here of improving the excavation efficiency for a conventional excavation obstacle such as a giant boulder or rock.

An object of the present invention is to eliminate the inconvenience of the prior art, eliminate the resistance on the rod during excavation, and to prevent the conventional excavation obstruction such as a huge boulder or rock bed. Excavation can be performed efficiently to increase work efficiency, reduce the consumption rate of the drilling head, shorten the construction period,
An object of the present invention is to provide an excavation method and an apparatus that can realize a complete excavation operation economically.

[0014]

According to the present invention, in order to achieve the above object, a drilling head having a drilling bit at a tip thereof is provided, and a propeller type stirring blade for generating an upward flow is drilled on the drilling head. The rod is provided at appropriate intervals in the circumferential direction of the rod and in the vertical direction so as to substantially overlap with the outer peripheral edge position of the head, and a vertical plate is bridged between vertically adjacent stirring blades appropriately selected from among these stirring blades. A stir / consolidation rod with an ironing plate attached thereto was connected, and a rod-shaped extension rod with no ironing plate and no stirring blade was continued on the stirring / consolidation rod. Using a drilling device incorporating a down-the-hole hammer in the drilling device by detecting it at the center position of the drilling head so as to line up with the drilling bit of the drilling head, and rotationally driving the whole, The excavated earth and sand from the drilling bit of the drilling head is raised by a stirring blade and carried to the outer surface of the ironing plate, and the ironing plate consolidates the hole wall so that the drilling resistance does not increase even if the drilling depth increases. The gist of the present invention is that drilling slips caused by the down-the-hole hammer are also pressed against the wall of the hole with an iron-painted plate so as not to be jetted to the ground.

According to the present invention, when the excavating head, the stirring / consolidating rod, and the extension rod are rotated and inserted into the ground to perform excavation, the earth and sand cut by the bit of the excavating head and the hammer head of the down-the-hole hammer. From the excavating head to the upper stirring / consolidation rod, is lifted by the stirring blades, goes to the outer peripheral surface of the ironing plate, and is condensed to the hole wall by the ironing plate.

In order to create a collapsed excavation hole, the porosity of the formation around the hole wall is reduced. By using the drilling device of the present invention in this way, excavated earth and sand is not discharged to the ground with a spiral screw as in the conventional method, but is pushed into the vicinity of a hole wall with a trowel, and the void ratio (porosity) is reduced. ), The hole wall will not collapse because of excavation. Also,
Excavated sediment does not discharge to the ground.

Therefore, the earth pressure (frictional resistance) applied to the rod
And the surface pressure of the excavation bit at the tip of the excavation head, which is important for excavation of the ground, can be adjusted. In particular, the rod above the stirring / consolidating rod is a rod-shaped extension rod with no iron coating plate and no stirring blade, so even if the depth is increased, the earth pressure (friction resistance) applied to the rod does not increase, and the drill bit is adjusted regardless of the depth. If it can be done, the drilling speed will be increased, the wear rate of the drill bit will be reduced, the construction period will be shortened, and the complete drilling operation will be economically possible.

In addition, since the peripheral speed of the drill bit of the drill head becomes slower toward the center, the drilling efficiency deteriorates. The present invention further incorporates a down-the-hole hammer to simultaneously excavate such a central part where the excavation efficiency is reduced with a down-the-hole hammer,
Excavation efficiency can be increased even in a place where a conventional excavation obstacle such as a giant boulder or a bedrock is formed.

In addition, the excavated dust from the down-the-hole hammer is transported to the stirring blades by an air lift without being carried to the ground by an air lift as in the conventional method. It is raised and all the holes are compacted with the ironing board.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a side view showing an embodiment of an excavation method and an apparatus according to the present invention, and FIG. 2 is a side view of a main part of the excavation method. The excavator according to the present invention will be described first.

The excavator according to the present invention comprises an excavating head 14 having a claw-shaped excavating bit 15 at its tip, a stirrer / consolidating rod 18 provided with a soldering plate 16 and a stirring blade 17 connected thereto. Further, as a connection on the stirring / consolidation rod 18, a rod-shaped extension rod 19 having no ironing plate and no stirring blade is provided.

The excavating head 14 has screw blades 20 for a half pitch symmetrically provided.

The agitating blade 17 of the agitating / consolidating rod 18 is of a propeller type which causes an upward flow. As shown in FIG. The rods were provided at appropriate intervals in the circumferential direction and the vertical direction so as to substantially overlap each other. (In the illustrated example, three sheets are arranged radially in a plan view.)

The iron coating plate 16 is formed by arranging a curved vertical plate between vertically adjacent stirring blades 17 appropriately selected from the stirring blades 17 in a shield shape. The iron coating plates 16 were arranged at equal intervals in the circumferential direction of the stirring / consolidating rod 18 and at a position where a spiral was drawn.

Further, the present invention incorporates a down-the-hole hammer 21 into such a drilling rig. The down-the-hole hammer 21 exposes the hammer head 22 at the center of the excavating head 14 so that the excavating bit surface 22a is aligned with the excavating bit 15 of the excavating head 14. As an example, when the excavation diameter of the excavation head 14 is about 500 φ, the excavation diameter of the hammer head 22 is about 200 φ.

Although not shown, a compressed air introduction path for driving the down-the-hole hammer 21 and a fluid introduction path for cement milk or the like are formed inside the stirring / consolidating rod 18 or the refill rod 19.

The excavator of the present invention has an upper end connected to a drive device 25 for moving up and down a leader 24 provided on the heavy equipment 23 and is driven to rotate downward from the drive device 25. And swivels 26a and 26b for liquid and liquid are provided, and hoses are connected to supply air and cement milk to the compressed air introduction path and the fluid introduction path such as cement milk.

Next, the excavation method of the present invention using such an excavator will be described. Drive the drive unit 25 to drive the drilling head 14, the stirring / consolidating rod 18, and the extension rod
If 19 is rotated, the whole is inserted by the excavation head 14 cutting into the ground.

At this time, the earth and sand cut on the excavating bit 15 of the excavating head 14 and the excavating bit surface 22a of the hammer head 22 of the down-the-hole hammer 21 reach the upper stirring / consolidation rod 18 from the excavating head 14 and have a propeller type. Stirrer blade 17
Is stirred while being sent as an upward flow, and goes to the outer peripheral surface of the ironing plate 16, where the ironing plate 16 consolidates the hole walls.

Usually, it is considered that this is due to the collapse motion of the earth pressure (friction resistance) soil particles applied to such a drilling rod. The relationship between the soil particles and the porosity is as follows. (A) Soil particles of 0.004 mm or less Porosity is 60 to 70% (B) Soil particles of 0.0048 to 1.9 mm or less Porosity is 35 to 50% (C) Soil particles 0mm or more Porosity is 25-40% (from boulder to boulder)

In order to form a borehole without collapse, the porosity of the stratum around the hole wall is reduced. By using the drilling device of the present invention in this way, the excavated earth and sand is not discharged to the ground with a spiral screw as in the prior art, but is pushed into the vicinity of the hole wall with the ironing plate 16, and the void ratio (gap) is reduced. Drilling while reducing the rate), the hole walls will not collapse. Excavated soil will not be discharged to the ground.

Therefore, the earth pressure (frictional resistance) applied to the stirring / consolidating rod 18 and the extension rod 19 is eliminated, and the drill bit 15 of the drill head 14 and the hammer head 22 of the down-the-hole hammer 21 which are important for the excavation of the ground. Adjustment of surface pressure of 22a can be measured. Drilling bit 15 and drilling bit surface 22a
If it can be adjusted, the excavation speed can be increased, the bit wear rate can be reduced, the construction period can be shortened, and the complete excavation work can be performed economically.

In the case where the excavation is normally performed smoothly, the frictional area of the stirring / consolidation rod 18 against the blades is constant even when the excavation depth is increased. No friction is applied to the.

[0034]

As described above, the excavation method and apparatus according to the present invention eliminate the resistance applied to the rod during excavation, and have a location where conventional excavation obstacles such as giant boulders and rocks are present. In addition, work efficiency can be improved by excavating efficiently, the consumption rate of the excavating head can be reduced, the construction period can be shortened, and economically complete excavation work can be realized.

[Brief description of the drawings]

FIG. 1 is an overall side view showing one embodiment of an excavation method and an excavation apparatus according to the present invention.

FIG. 2 is a side view of a main part of one embodiment of the excavator according to the present invention.

FIG. 3 is a plan view showing an arrangement of a stirring blade.

FIG. 4 is a side view of a conventional earth auger.

FIG. 5 is a side view of a main part showing a conventional example of a downhole hammer.

FIG. 6 is a side view of a main part showing another conventional example of a downhole hammer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Heavy machine 2 ... Leader mast 3 ... Top sheave 4 ... Drive device 5, 5 '... Screw rod 5a ... Rod 5b ... Screw blade 6 ... Auger head 7 ... Winch 8 ... Body part 9 ... Spiral blade 10a ... Compressed air inlet 10b ... Fluid inlet 11 ... Hammer head 12 ... Support plate 13 ... Drilling bit 14 ... Drilling head 15 ... Drilling bit 16 ... Iron coating plate 17 ... Stirring blade 18 ... Stirring / consolidation rod 19 ... Refill rod 20 ... Screw blade 21 ... Down the hole hammer 22 ... Hammer head 22a ... Drilling bit surface 23 ... Heavy machinery 24 ... Leader 25 ... Driver 26a, 26b ... Swivel 27 ... Stabilizer

Claims (2)

[Claims] 1. A drilling head having a drilling bit at a tip thereof is provided, and a propeller-type agitating blade for generating an upward flow is provided on the drilling head such that the tip thereof substantially overlaps an outer peripheral edge position of the drilling head. Provided at appropriate intervals in the circumferential direction and up and down direction, connecting the stirring and consolidation rods attached ironing plate obtained by bridging a vertical plate between vertically adjacent stirring blades appropriately selected among these stirring blades, Further, a rod-shaped extension rod having no ironing plate and no stirring blade is continued on the stirring / consolidation rod, and the hammer head is positioned at the center of the drilling head so that the drilling bit surface is aligned with the drilling bit of the drilling head. Using a drilling rig that is exposed to the down-the-hole hammer and built into the drilling rig,
The whole is rotated and the excavated earth and sand from the excavation bit of the excavation head is lifted by the stirring blade and transported to the outer surface of the ironing plate, and the ironing plate consolidates the hole wall to increase the excavation resistance even if the excavation depth increases. An excavation method in which the excavation with a down-the-hole hammer is compacted to the wall of the hole with a trowel, so that it does not spill onto the ground. 2. A drilling head having a drilling bit at a tip thereof is provided with a propeller-type agitating blade for generating an ascending flow, the tip of which is substantially overlapped with the outer peripheral edge position of the drilling head. Provided at appropriate intervals in the circumferential direction and up and down direction, connecting the stirring and consolidation rods attached ironing plate obtained by bridging a vertical plate between vertically adjacent stirring blades appropriately selected among these stirring blades, Further, a rod-shaped extension rod having no ironing plate and no stirring blade is continued on the stirring / consolidation rod, and the hammer head is positioned at the center of the drilling head so that the drilling bit surface is aligned with the drilling bit of the drilling head. An excavator wherein a down-the-hole hammer is detected and incorporated into the excavator.